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YAMLValidator.dev
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YAML
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JSON Formatter & Validator
KuberLogic
YAML Validator is a free, privacy-first tool for validating, formatting, and viewing YAML files โ available as a Chrome extension and a website.
---Paste or type YAML into the editor. YAML Validator auto-detects the schema (e.g., spots apiVersion + kind and picks Kubernetes) and validates both syntax and structure in one click. If the detected schema doesn't match, it suggests the right one with a single-click switch.
Everything runs client-side โ your files never leave your machine. No accounts, no server processing, no data collection. Works offline, loads instantly.
Whether you're writing Kubernetes manifests, debugging a CI pipeline, or reviewing a Helm chart on GitHub โ YAML Validator catches errors before they reach production. The Chrome extension currently has around 800 users worldwide.
Available in 54 languages.
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YAMLValidator.dev's answer:
It validates YAML against real schemas โ generic YAML, Kubernetes, Docker Compose, GitHub Actions, GitLab CI, Helm, OpenAPI, and more โ not just syntax checking. Everything runs client-side, so your config files never leave your machine. It works both as a Chrome extension (with GitHub integration for collapsible code blocks) and as a standalone website.
YAMLValidator.dev's answer:
DevOps engineers, SREs, and backend developers who work with Kubernetes manifests, Docker Compose files, CI/CD pipelines (GitHub Actions, GitLab CI, CircleCI, Azure Pipelines), Helm charts, and OpenAPI specs. Anyone who edits YAML config files and wants instant validation without leaving the browser.
YAMLValidator.dev's answer:
I am software engineer and extension(and lately site) was made out of frustration with debugging YAML indentation errors in CircleCI schemes and Kubernetes deployments. A misplaced space in a YAML file can break an entire deployment, and generic text editors don't catch schema-level mistakes. YAML Validator was built to catch those errors before they reach production โ directly in the browser, with zero setup.
YAMLValidator.dev's answer:
JavaScript/TypeScript, CodeMirror (editor), js-yaml (parsing), Ajv (JSON Schema validation), Lit (web components), and Tailwind CSS. Built as a Chrome Extension (Manifest V3) with Vite as the bundler. Schemas are pre-compiled at build time for performance and CSP compliance
YAMLValidator.dev's answer:
YAML Validator is a free, open-use tool โ it doesn't track users or require accounts. It's used by individual developers and teams working with Kubernetes, Docker, and CI/CD pipelines. As a privacy-first browser tool, there's no customer list by design. The browser extension currently has around 800 users worldwide.
YAMLValidator.dev's answer:
There's simply no other Chrome extension that does this. Most online YAML tools are web-only, require an internet connection, and only check syntax. YAML Validator runs entirely offline, validates against 11+ schemas with auto-detection (Kubernetes, Docker Compose, GitHub Actions, and more), and enriches GitHub with collapsible code blocks for YAML files. It's fast, private, and requires zero setup โ install and go.
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yamlfmt - An extensible command line tool or library to format yaml files. - GitHub - google/yamlfmt: An extensible command line tool or library to format yaml files.